Merge pull request #2813 from diondokter/u0-dion

More U0 support

ci.sh

@@ -189,6 +189,7 @@ cargo batch \
     --- build --release --manifest-path examples/stm32l1/Cargo.toml --target thumbv7m-none-eabi --out-dir out/examples/stm32l1 \
     --- build --release --manifest-path examples/stm32l4/Cargo.toml --target thumbv7em-none-eabi --out-dir out/examples/stm32l4 \
     --- build --release --manifest-path examples/stm32l5/Cargo.toml --target thumbv8m.main-none-eabihf --out-dir out/examples/stm32l5 \
+    --- build --release --manifest-path examples/stm32u0/Cargo.toml --target thumbv6m-none-eabi --out-dir out/examples/stm32u0 \
     --- build --release --manifest-path examples/stm32u5/Cargo.toml --target thumbv8m.main-none-eabihf --out-dir out/examples/stm32u5 \
     --- build --release --manifest-path examples/stm32wb/Cargo.toml --target thumbv7em-none-eabi --out-dir out/examples/stm32wb \
     --- build --release --manifest-path examples/stm32wba/Cargo.toml --target thumbv8m.main-none-eabihf --out-dir out/examples/stm32wba \

embassy-stm32/Cargo.toml

@@ -71,7 +71,7 @@ rand_core = "0.6.3"
 sdio-host = "0.5.0"
 critical-section = "1.1"
 #stm32-metapac = { version = "15" }
-stm32-metapac = { git = "https://github.com/embassy-rs/stm32-data-generated", tag = "stm32-data-d674277b78ca7400ecfeeb1b5af4e460a65c1a61" }
+stm32-metapac = { git = "https://github.com/embassy-rs/stm32-data-generated", tag = "stm32-data-01ac9bfd035961dc75f32dcd6080501538246d5c" }
 
 vcell = "0.1.3"
 nb = "1.0.0"
@@ -97,7 +97,7 @@ proc-macro2 = "1.0.36"
 quote = "1.0.15"
 
 #stm32-metapac = { version = "15", default-features = false, features = ["metadata"]}
-stm32-metapac = { git = "https://github.com/embassy-rs/stm32-data-generated", tag = "stm32-data-d674277b78ca7400ecfeeb1b5af4e460a65c1a61", default-features = false, features = ["metadata"]}
+stm32-metapac = { git = "https://github.com/embassy-rs/stm32-data-generated", tag = "stm32-data-01ac9bfd035961dc75f32dcd6080501538246d5c", default-features = false, features = ["metadata"]}
 
 [features]
 default = ["rt"]

embassy-stm32/src/adc/mod.rs

@@ -10,7 +10,7 @@
 #[cfg_attr(adc_v1, path = "v1.rs")]
 #[cfg_attr(adc_l0, path = "v1.rs")]
 #[cfg_attr(adc_v2, path = "v2.rs")]
-#[cfg_attr(any(adc_v3, adc_g0, adc_h5), path = "v3.rs")]
+#[cfg_attr(any(adc_v3, adc_g0, adc_h5, adc_u0), path = "v3.rs")]
 #[cfg_attr(adc_v4, path = "v4.rs")]
 #[cfg_attr(adc_g4, path = "g4.rs")]
 mod _version;
@@ -96,6 +96,7 @@ pub(crate) fn blocking_delay_us(us: u32) {
     adc_f3,
     adc_f3_v1_1,
     adc_g0,
+    adc_u0,
     adc_h5
 )))]
 #[allow(private_bounds)]
@@ -114,6 +115,7 @@ pub trait Instance: SealedInstance + crate::Peripheral<P = Self> {
     adc_f3,
     adc_f3_v1_1,
     adc_g0,
+    adc_u0,
     adc_h5
 ))]
 #[allow(private_bounds)]

embassy-stm32/src/adc/v3.rs

@@ -19,6 +19,8 @@ impl<T: Instance> super::SealedAdcPin<T> for VrefInt {
                 let val = 13;
             } else if #[cfg(adc_h5)] {
                 let val = 17;
+            } else if #[cfg(adc_u0)] {
+                let val = 12;
             } else {
                 let val = 0;
             }
@@ -36,6 +38,8 @@ impl<T: Instance> super::SealedAdcPin<T> for Temperature {
                 let val = 12;
             } else if #[cfg(adc_h5)] {
                 let val = 16;
+            } else if #[cfg(adc_u0)] {
+                let val = 11;
             } else {
                 let val = 17;
             }
@@ -53,6 +57,8 @@ impl<T: Instance> super::SealedAdcPin<T> for Vbat {
                 let val = 14;
             } else if #[cfg(adc_h5)] {
                 let val = 2;
+            } else if #[cfg(adc_h5)] {
+                let val = 13;
             } else {
                 let val = 18;
             }
@@ -73,17 +79,29 @@ cfg_if! {
     }
 }
 
+cfg_if! {
+    if #[cfg(adc_u0)] {
+        pub struct DacOut;
+        impl<T: Instance> AdcPin<T> for DacOut {}
+        impl<T: Instance> super::SealedAdcPin<T> for DacOut {
+            fn channel(&self) -> u8 {
+                19
+            }
+        }
+    }
+}
+
 impl<'d, T: Instance> Adc<'d, T> {
     pub fn new(adc: impl Peripheral<P = T> + 'd) -> Self {
         into_ref!(adc);
         T::enable_and_reset();
         T::regs().cr().modify(|reg| {
-            #[cfg(not(adc_g0))]
+            #[cfg(not(any(adc_g0, adc_u0)))]
             reg.set_deeppwd(false);
             reg.set_advregen(true);
         });
 
-        #[cfg(adc_g0)]
+        #[cfg(any(adc_g0, adc_u0))]
         T::regs().cfgr1().modify(|reg| {
             reg.set_chselrmod(false);
         });
@@ -107,11 +125,11 @@ impl<'d, T: Instance> Adc<'d, T> {
     }
 
     pub fn enable_vrefint(&self) -> VrefInt {
-        #[cfg(not(adc_g0))]
+        #[cfg(not(any(adc_g0, adc_u0)))]
         T::common_regs().ccr().modify(|reg| {
             reg.set_vrefen(true);
         });
-        #[cfg(adc_g0)]
+        #[cfg(any(adc_g0, adc_u0))]
         T::regs().ccr().modify(|reg| {
             reg.set_vrefen(true);
         });
@@ -125,7 +143,7 @@ impl<'d, T: Instance> Adc<'d, T> {
 
     pub fn enable_temperature(&self) -> Temperature {
         cfg_if! {
-            if #[cfg(adc_g0)] {
+            if #[cfg(any(adc_g0, adc_u0))] {
                 T::regs().ccr().modify(|reg| {
                     reg.set_tsen(true);
                 });
@@ -145,7 +163,7 @@ impl<'d, T: Instance> Adc<'d, T> {
 
     pub fn enable_vbat(&self) -> Vbat {
         cfg_if! {
-            if #[cfg(adc_g0)] {
+            if #[cfg(any(adc_g0, adc_u0))] {
                 T::regs().ccr().modify(|reg| {
                     reg.set_vbaten(true);
                 });
@@ -168,9 +186,9 @@ impl<'d, T: Instance> Adc<'d, T> {
     }
 
     pub fn set_resolution(&mut self, resolution: Resolution) {
-        #[cfg(not(adc_g0))]
+        #[cfg(not(any(adc_g0, adc_u0)))]
         T::regs().cfgr().modify(|reg| reg.set_res(resolution.into()));
-        #[cfg(adc_g0)]
+        #[cfg(any(adc_g0, adc_u0))]
         T::regs().cfgr1().modify(|reg| reg.set_res(resolution.into()));
     }
 
@@ -231,9 +249,9 @@ impl<'d, T: Instance> Adc<'d, T> {
         Self::set_channel_sample_time(pin.channel(), self.sample_time);
 
         // Select channel
-        #[cfg(not(adc_g0))]
+        #[cfg(not(any(adc_g0, adc_u0)))]
         T::regs().sqr1().write(|reg| reg.set_sq(0, pin.channel()));
-        #[cfg(adc_g0)]
+        #[cfg(any(adc_g0, adc_u0))]
         T::regs().chselr().write(|reg| reg.set_chsel(1 << pin.channel()));
 
         // Some models are affected by an erratum:
@@ -261,7 +279,7 @@ impl<'d, T: Instance> Adc<'d, T> {
 
     fn set_channel_sample_time(_ch: u8, sample_time: SampleTime) {
         cfg_if! {
-            if #[cfg(adc_g0)] {
+            if #[cfg(any(adc_g0, adc_u0))] {
                 T::regs().smpr().modify(|reg| reg.set_smp1(sample_time.into()));
             } else if #[cfg(adc_h5)] {
                 match _ch {

embassy-stm32/src/crc/v2v3.rs

@@ -13,6 +13,8 @@ pub struct Crc<'d> {
 }
 
 /// CRC configuration errlr
+#[derive(Debug)]
+#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 pub enum ConfigError {
     /// The selected polynomial is invalid.
     InvalidPolynomial,

embassy-stm32/src/dac/tsel.rs

@@ -235,6 +235,23 @@ pub enum TriggerSel {
     Exti9 = 13,
 }
 
+/// Trigger selection for U0.
+#[cfg(stm32u0)]
+#[derive(Debug, Copy, Clone, Eq, PartialEq)]
+#[cfg_attr(feature = "defmt", derive(defmt::Format))]
+pub enum TriggerSel {
+    Software = 0,
+    Tim1 = 1,
+    Tim2 = 2,
+    Tim3 = 3,
+    Tim6 = 5,
+    Tim7 = 6,
+    Tim15 = 8,
+    Lptim1 = 11,
+    Lptim2 = 12,
+    Exti9 = 14,
+}
+
 /// Trigger selection for G4.
 #[cfg(stm32g4)]
 #[derive(Debug, Copy, Clone, Eq, PartialEq)]

embassy-stm32/src/flash/mod.rs

@@ -101,10 +101,11 @@ pub enum FlashBank {
 #[cfg_attr(flash_h7ab, path = "h7.rs")]
 #[cfg_attr(flash_u5, path = "u5.rs")]
 #[cfg_attr(flash_h50, path = "h50.rs")]
+#[cfg_attr(flash_u0, path = "u0.rs")]
 #[cfg_attr(
     not(any(
         flash_l0, flash_l1, flash_l4, flash_wl, flash_wb, flash_f0, flash_f1, flash_f3, flash_f4, flash_f7, flash_g0,
-        flash_g4, flash_h7, flash_h7ab, flash_u5, flash_h50
+        flash_g4, flash_h7, flash_h7ab, flash_u5, flash_h50, flash_u0
     )),
     path = "other.rs"
 )]

embassy-stm32/src/flash/u0.rs

@@ -0,0 +1,96 @@
+use core::ptr::write_volatile;
+use core::sync::atomic::{fence, Ordering};
+
+use cortex_m::interrupt;
+
+use super::{FlashRegion, FlashSector, FLASH_REGIONS, WRITE_SIZE};
+use crate::flash::Error;
+use crate::pac;
+
+pub(crate) const fn is_default_layout() -> bool {
+    true
+}
+
+pub(crate) const fn get_flash_regions() -> &'static [&'static FlashRegion] {
+    &FLASH_REGIONS
+}
+
+pub(crate) unsafe fn lock() {
+    pac::FLASH.cr().modify(|w| w.set_lock(true));
+}
+pub(crate) unsafe fn unlock() {
+    // Wait, while the memory interface is busy.
+    while pac::FLASH.sr().read().bsy1() {}
+
+    // Unlock flash
+    if pac::FLASH.cr().read().lock() {
+        pac::FLASH.keyr().write(|w| w.set_key(0x4567_0123));
+        pac::FLASH.keyr().write(|w| w.set_key(0xCDEF_89AB));
+    }
+}
+
+pub(crate) unsafe fn enable_blocking_write() {
+    assert_eq!(0, WRITE_SIZE % 4);
+    pac::FLASH.cr().write(|w| w.set_pg(true));
+}
+
+pub(crate) unsafe fn disable_blocking_write() {
+    pac::FLASH.cr().write(|w| w.set_pg(false));
+}
+
+pub(crate) unsafe fn blocking_write(start_address: u32, buf: &[u8; WRITE_SIZE]) -> Result<(), Error> {
+    let mut address = start_address;
+    for val in buf.chunks(4) {
+        write_volatile(address as *mut u32, u32::from_le_bytes(val.try_into().unwrap()));
+        address += val.len() as u32;
+
+        // prevents parallelism errors
+        fence(Ordering::SeqCst);
+    }
+
+    wait_ready_blocking()
+}
+
+pub(crate) unsafe fn blocking_erase_sector(sector: &FlashSector) -> Result<(), Error> {
+    let idx = (sector.start - super::FLASH_BASE as u32) / super::BANK1_REGION.erase_size as u32;
+    while pac::FLASH.sr().read().bsy1() {}
+    clear_all_err();
+
+    interrupt::free(|_| {
+        pac::FLASH.cr().modify(|w| {
+            w.set_per(true);
+            w.set_pnb(idx as u8);
+            w.set_strt(true);
+        });
+    });
+
+    let ret: Result<(), Error> = wait_ready_blocking();
+    pac::FLASH.cr().modify(|w| w.set_per(false));
+    ret
+}
+
+pub(crate) unsafe fn wait_ready_blocking() -> Result<(), Error> {
+    while pac::FLASH.sr().read().bsy1() {}
+
+    let sr = pac::FLASH.sr().read();
+
+    if sr.progerr() {
+        return Err(Error::Prog);
+    }
+
+    if sr.wrperr() {
+        return Err(Error::Protected);
+    }
+
+    if sr.pgaerr() {
+        return Err(Error::Unaligned);
+    }
+
+    Ok(())
+}
+
+pub(crate) unsafe fn clear_all_err() {
+    // read and write back the same value.
+    // This clears all "write 1 to clear" bits.
+    pac::FLASH.sr().modify(|_| {});
+}

embassy-stm32/src/usb/mod.rs

@@ -23,7 +23,7 @@ fn common_init<T: Instance>() {
         )
     }
 
-    #[cfg(any(stm32l4, stm32l5, stm32wb))]
+    #[cfg(any(stm32l4, stm32l5, stm32wb, stm32u0))]
     critical_section::with(|_| crate::pac::PWR.cr2().modify(|w| w.set_usv(true)));
 
     #[cfg(pwr_h5)]

embassy-stm32/src/usb/usb.rs

@@ -107,14 +107,14 @@ const EP_COUNT: usize = 8;
 
 #[cfg(any(usbram_16x1_512, usbram_16x2_512))]
 const USBRAM_SIZE: usize = 512;
-#[cfg(usbram_16x2_1024)]
+#[cfg(any(usbram_16x2_1024, usbram_32_1024))]
 const USBRAM_SIZE: usize = 1024;
 #[cfg(usbram_32_2048)]
 const USBRAM_SIZE: usize = 2048;
 
-#[cfg(not(usbram_32_2048))]
+#[cfg(not(any(usbram_32_2048, usbram_32_1024)))]
 const USBRAM_ALIGN: usize = 2;
-#[cfg(usbram_32_2048)]
+#[cfg(any(usbram_32_2048, usbram_32_1024))]
 const USBRAM_ALIGN: usize = 4;
 
 const NEW_AW: AtomicWaker = AtomicWaker::new();
@@ -159,7 +159,7 @@ fn calc_out_len(len: u16) -> (u16, u16) {
     }
 }
 
-#[cfg(not(usbram_32_2048))]
+#[cfg(not(any(usbram_32_2048, usbram_32_1024)))]
 mod btable {
     use super::*;
 
@@ -180,7 +180,7 @@ mod btable {
         USBRAM.mem(index * 4 + 3).read()
     }
 }
-#[cfg(usbram_32_2048)]
+#[cfg(any(usbram_32_2048, usbram_32_1024))]
 mod btable {
     use super::*;
 
@@ -224,9 +224,9 @@ impl<T: Instance> EndpointBuffer<T> {
             let n = USBRAM_ALIGN.min(buf.len() - i * USBRAM_ALIGN);
             val[..n].copy_from_slice(&buf[i * USBRAM_ALIGN..][..n]);
 
-            #[cfg(not(usbram_32_2048))]
+            #[cfg(not(any(usbram_32_2048, usbram_32_1024)))]
             let val = u16::from_le_bytes(val);
-            #[cfg(usbram_32_2048)]
+            #[cfg(any(usbram_32_2048, usbram_32_1024))]
             let val = u32::from_le_bytes(val);
             USBRAM.mem(self.addr as usize / USBRAM_ALIGN + i).write_value(val);
         }

examples/stm32u0/Cargo.toml

@@ -6,10 +6,11 @@ license = "MIT OR Apache-2.0"
 
 [dependencies]
 # Change stm32u083rc to your chip name, if necessary.
-embassy-stm32 = { version = "0.1.0", path = "../../embassy-stm32", features = [ "defmt", "time-driver-any", "stm32u083rc", "memory-x", "unstable-pac", "exti"]  }
+embassy-stm32 = { version = "0.1.0", path = "../../embassy-stm32", features = [ "defmt", "time-driver-any", "stm32u083rc", "memory-x", "unstable-pac", "exti", "chrono"]  }
 embassy-sync = { version = "0.5.0", path = "../../embassy-sync", features = ["defmt"] }
 embassy-executor = { version = "0.5.0", path = "../../embassy-executor", features = ["arch-cortex-m", "executor-thread", "defmt", "integrated-timers"] }
 embassy-time = { version = "0.3.0", path = "../../embassy-time", features = ["defmt", "defmt-timestamp-uptime", "tick-hz-32_768"] }
+embassy-usb = { version = "0.1.0", path = "../../embassy-usb", default-features = false, features = ["defmt"] }
 
 defmt = "0.3"
 defmt-rtt = "0.4"
@@ -21,5 +22,8 @@ panic-probe = { version = "0.3", features = ["print-defmt"] }
 futures = { version = "0.3.17", default-features = false, features = ["async-await"] }
 heapless = { version = "0.8", default-features = false }
 
+micromath = "2.0.0"
+chrono = { version = "0.4.38", default-features = false }
+
 [profile.release]
 debug = 2

examples/stm32u0/src/bin/adc.rs

@@ -0,0 +1,30 @@
+#![no_std]
+#![no_main]
+
+use defmt::*;
+use embassy_stm32::adc::{Adc, Resolution};
+use embassy_stm32::Config;
+use embassy_time::Duration;
+use {defmt_rtt as _, panic_probe as _};
+
+#[cortex_m_rt::entry]
+fn main() -> ! {
+    info!("Hello World!");
+
+    let mut config = Config::default();
+    {
+        use embassy_stm32::rcc::*;
+        config.rcc.mux.adcsel = mux::Adcsel::SYS;
+    }
+    let p = embassy_stm32::init(config);
+
+    let mut adc = Adc::new(p.ADC1);
+    adc.set_resolution(Resolution::BITS8);
+    let mut channel = p.PC0;
+
+    loop {
+        let v = adc.read(&mut channel);
+        info!("--> {}", v);
+        embassy_time::block_for(Duration::from_millis(200));
+    }
+}

examples/stm32u0/src/bin/crc.rs

@@ -0,0 +1,31 @@
+#![no_std]
+#![no_main]
+
+use defmt::*;
+use embassy_executor::Spawner;
+use embassy_stm32::crc::{Config, Crc, InputReverseConfig, PolySize};
+use {defmt_rtt as _, panic_probe as _};
+
+#[embassy_executor::main]
+async fn main(_spawner: Spawner) {
+    let p = embassy_stm32::init(Default::default());
+    info!("Hello World!");
+
+    // Setup for: https://crccalc.com/?crc=Life, it never dieWomen are my favorite guy&method=crc32&datatype=ascii&outtype=0
+    let mut crc = Crc::new(
+        p.CRC,
+        unwrap!(Config::new(
+            InputReverseConfig::Byte,
+            true,
+            PolySize::Width32,
+            0xFFFFFFFF,
+            0x04C11DB7
+        )),
+    );
+
+    let output = crc.feed_bytes(b"Life, it never die\nWomen are my favorite guy") ^ 0xFFFFFFFF;
+
+    defmt::assert_eq!(output, 0x33F0E26B);
+
+    cortex_m::asm::bkpt();
+}

examples/stm32u0/src/bin/dac.rs

@@ -0,0 +1,35 @@
+#![no_std]
+#![no_main]
+
+use defmt::*;
+use embassy_stm32::dac::{DacCh1, Value};
+use embassy_stm32::dma::NoDma;
+use {defmt_rtt as _, panic_probe as _};
+
+#[cortex_m_rt::entry]
+fn main() -> ! {
+    let p = embassy_stm32::init(Default::default());
+    info!("Hello World!");
+
+    let mut dac = DacCh1::new(p.DAC1, NoDma, p.PA4);
+
+    loop {
+        for v in 0..=255 {
+            dac.set(Value::Bit8(to_sine_wave(v)));
+        }
+    }
+}
+
+use micromath::F32Ext;
+
+fn to_sine_wave(v: u8) -> u8 {
+    if v >= 128 {
+        // top half
+        let r = 3.14 * ((v - 128) as f32 / 128.0);
+        (r.sin() * 128.0 + 127.0) as u8
+    } else {
+        // bottom half
+        let r = 3.14 + 3.14 * (v as f32 / 128.0);
+        (r.sin() * 128.0 + 127.0) as u8
+    }
+}

examples/stm32u0/src/bin/flash.rs

@@ -0,0 +1,43 @@
+#![no_std]
+#![no_main]
+
+use defmt::*;
+use embassy_executor::Spawner;
+use embassy_stm32::flash::Flash;
+use {defmt_rtt as _, panic_probe as _};
+
+#[embassy_executor::main]
+async fn main(_spawner: Spawner) {
+    let p = embassy_stm32::init(Default::default());
+    info!("Hello World!");
+
+    let addr: u32 = 0x40000 - 2 * 1024;
+
+    let mut f = Flash::new_blocking(p.FLASH).into_blocking_regions().bank1_region;
+
+    info!("Reading...");
+    let mut buf = [0u8; 32];
+    unwrap!(f.blocking_read(addr, &mut buf));
+    info!("Read: {=[u8]:x}", buf);
+    info!("Erasing...");
+    unwrap!(f.blocking_erase(addr, addr + 2 * 1024));
+
+    info!("Reading...");
+    let mut buf = [0u8; 32];
+    unwrap!(f.blocking_read(addr, &mut buf));
+    info!("Read after erase: {=[u8]:x}", buf);
+
+    info!("Writing...");
+    unwrap!(f.blocking_write(
+        addr,
+        &[
+            1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29,
+            30, 31, 32
+        ]
+    ));
+
+    info!("Reading...");
+    let mut buf = [0u8; 32];
+    unwrap!(f.blocking_read(addr, &mut buf));
+    info!("Read: {=[u8]:x}", buf);
+}

examples/stm32u0/src/bin/i2c.rs

@@ -0,0 +1,21 @@
+#![no_std]
+#![no_main]
+
+use defmt::*;
+use embassy_executor::Spawner;
+use embassy_stm32::i2c::I2c;
+use embassy_stm32::time::Hertz;
+use {defmt_rtt as _, panic_probe as _};
+
+const ADDRESS: u8 = 0x5F;
+const WHOAMI: u8 = 0x0F;
+
+#[embassy_executor::main]
+async fn main(_spawner: Spawner) {
+    let p = embassy_stm32::init(Default::default());
+    let mut i2c = I2c::new_blocking(p.I2C2, p.PB10, p.PB11, Hertz(100_000), Default::default());
+
+    let mut data = [0u8; 1];
+    unwrap!(i2c.blocking_write_read(ADDRESS, &[WHOAMI], &mut data));
+    info!("Whoami: {}", data[0]);
+}

examples/stm32u0/src/bin/rng.rs

@@ -0,0 +1,43 @@
+#![no_std]
+#![no_main]
+
+use defmt::*;
+use embassy_executor::Spawner;
+use embassy_stm32::rcc::mux::Clk48sel;
+use embassy_stm32::rng::Rng;
+use embassy_stm32::{bind_interrupts, peripherals, rng, Config};
+use {defmt_rtt as _, panic_probe as _};
+
+bind_interrupts!(struct Irqs {
+    RNG_CRYP => rng::InterruptHandler<peripherals::RNG>;
+});
+
+#[embassy_executor::main]
+async fn main(_spawner: Spawner) {
+    let mut config = Config::default();
+    {
+        use embassy_stm32::rcc::*;
+        config.rcc.hsi = true;
+        config.rcc.pll = Some(Pll {
+            source: PllSource::HSI, // 16 MHz
+            prediv: PllPreDiv::DIV1,
+            mul: PllMul::MUL7, // 16 * 7 = 112 MHz
+            divp: None,
+            divq: None,
+            divr: Some(PllRDiv::DIV2), // 112 / 2 = 56 MHz
+        });
+        config.rcc.sys = Sysclk::PLL1_R;
+        config.rcc.hsi48 = Some(Hsi48Config { sync_from_usb: false }); // needed for RNG
+        config.rcc.mux.clk48sel = Clk48sel::HSI48; // needed for RNG (or use MSI or PLLQ if you want)
+    }
+
+    let p = embassy_stm32::init(config);
+
+    info!("Hello World!");
+
+    let mut rng = Rng::new(p.RNG, Irqs);
+
+    let mut buf = [0u8; 16];
+    unwrap!(rng.async_fill_bytes(&mut buf).await);
+    info!("random bytes: {:02x}", buf);
+}

examples/stm32u0/src/bin/rtc.rs

@@ -0,0 +1,49 @@
+#![no_std]
+#![no_main]
+
+use chrono::{NaiveDate, NaiveDateTime};
+use defmt::*;
+use embassy_executor::Spawner;
+use embassy_stm32::rtc::{Rtc, RtcConfig};
+use embassy_stm32::Config;
+use embassy_time::Timer;
+use {defmt_rtt as _, panic_probe as _};
+
+#[embassy_executor::main]
+async fn main(_spawner: Spawner) {
+    let mut config = Config::default();
+    {
+        use embassy_stm32::rcc::*;
+        config.rcc.sys = Sysclk::PLL1_R;
+        config.rcc.hsi = true;
+        config.rcc.pll = Some(Pll {
+            source: PllSource::HSI, // 16 MHz
+            prediv: PllPreDiv::DIV1,
+            mul: PllMul::MUL7, // 16 * 7 = 112 MHz
+            divp: None,
+            divq: None,
+            divr: Some(PllRDiv::DIV2), // 112 / 2 = 56 MHz
+        });
+        config.rcc.ls = LsConfig::default();
+    }
+
+    let p = embassy_stm32::init(config);
+
+    info!("Hello World!");
+
+    let now = NaiveDate::from_ymd_opt(2020, 5, 15)
+        .unwrap()
+        .and_hms_opt(10, 30, 15)
+        .unwrap();
+
+    let mut rtc = Rtc::new(p.RTC, RtcConfig::default());
+    info!("Got RTC! {:?}", now.and_utc().timestamp());
+
+    rtc.set_datetime(now.into()).expect("datetime not set");
+
+    // In reality the delay would be much longer
+    Timer::after_millis(20000).await;
+
+    let then: NaiveDateTime = rtc.now().unwrap().into();
+    info!("Got RTC! {:?}", then.and_utc().timestamp());
+}

examples/stm32u0/src/bin/spi.rs

@@ -0,0 +1,30 @@
+#![no_std]
+#![no_main]
+
+use defmt::*;
+use embassy_stm32::gpio::{Level, Output, Speed};
+use embassy_stm32::spi::{Config, Spi};
+use embassy_stm32::time::Hertz;
+use {defmt_rtt as _, panic_probe as _};
+
+#[cortex_m_rt::entry]
+fn main() -> ! {
+    info!("Hello World!");
+
+    let p = embassy_stm32::init(Default::default());
+
+    let mut spi_config = Config::default();
+    spi_config.frequency = Hertz(1_000_000);
+
+    let mut spi = Spi::new_blocking(p.SPI3, p.PC10, p.PC12, p.PC11, spi_config);
+
+    let mut cs = Output::new(p.PE0, Level::High, Speed::VeryHigh);
+
+    loop {
+        let mut buf = [0x0Au8; 4];
+        cs.set_low();
+        unwrap!(spi.blocking_transfer_in_place(&mut buf));
+        cs.set_high();
+        info!("xfer {=[u8]:x}", buf);
+    }
+}

examples/stm32u0/src/bin/usart.rs

@@ -0,0 +1,25 @@
+#![no_std]
+#![no_main]
+
+use defmt::*;
+use embassy_stm32::usart::{Config, Uart};
+use {defmt_rtt as _, panic_probe as _};
+
+#[cortex_m_rt::entry]
+fn main() -> ! {
+    info!("Hello World!");
+
+    let p = embassy_stm32::init(Default::default());
+
+    let config = Config::default();
+    let mut usart = Uart::new_blocking(p.USART2, p.PA3, p.PA2, config).unwrap();
+
+    unwrap!(usart.blocking_write(b"Hello Embassy World!\r\n"));
+    info!("wrote Hello, starting echo");
+
+    let mut buf = [0u8; 1];
+    loop {
+        unwrap!(usart.blocking_read(&mut buf));
+        unwrap!(usart.blocking_write(&buf));
+    }
+}

examples/stm32u0/src/bin/usb_serial.rs

@@ -0,0 +1,109 @@
+#![no_std]
+#![no_main]
+
+use defmt::{panic, *};
+use defmt_rtt as _; // global logger
+use embassy_executor::Spawner;
+use embassy_stm32::usb::{Driver, Instance};
+use embassy_stm32::{bind_interrupts, peripherals, usb, Config};
+use embassy_usb::class::cdc_acm::{CdcAcmClass, State};
+use embassy_usb::driver::EndpointError;
+use embassy_usb::Builder;
+use futures::future::join;
+use panic_probe as _;
+
+bind_interrupts!(struct Irqs {
+    USB_DRD_FS => usb::InterruptHandler<peripherals::USB>;
+});
+
+#[embassy_executor::main]
+async fn main(_spawner: Spawner) {
+    let mut config = Config::default();
+    {
+        use embassy_stm32::rcc::*;
+        config.rcc.hsi = true;
+        config.rcc.pll = Some(Pll {
+            source: PllSource::HSI, // 16 MHz
+            prediv: PllPreDiv::DIV1,
+            mul: PllMul::MUL7,
+            divp: None,
+            divq: None,
+            divr: Some(PllRDiv::DIV2), // 56 MHz
+        });
+        config.rcc.sys = Sysclk::PLL1_R;
+        config.rcc.hsi48 = Some(Hsi48Config { sync_from_usb: true }); // needed for USB
+        config.rcc.mux.clk48sel = mux::Clk48sel::HSI48; // USB uses ICLK
+    }
+
+    let p = embassy_stm32::init(config);
+
+    info!("Hello World!");
+
+    // Create the driver, from the HAL.
+    let driver = Driver::new(p.USB, Irqs, p.PA12, p.PA11);
+
+    // Create embassy-usb Config
+    let config = embassy_usb::Config::new(0xc0de, 0xcafe);
+    //config.max_packet_size_0 = 64;
+
+    // Create embassy-usb DeviceBuilder using the driver and config.
+    // It needs some buffers for building the descriptors.
+    let mut config_descriptor = [0; 256];
+    let mut bos_descriptor = [0; 256];
+    let mut control_buf = [0; 7];
+
+    let mut state = State::new();
+
+    let mut builder = Builder::new(
+        driver,
+        config,
+        &mut config_descriptor,
+        &mut bos_descriptor,
+        &mut [], // no msos descriptors
+        &mut control_buf,
+    );
+
+    // Create classes on the builder.
+    let mut class = CdcAcmClass::new(&mut builder, &mut state, 64);
+
+    // Build the builder.
+    let mut usb = builder.build();
+
+    // Run the USB device.
+    let usb_fut = usb.run();
+
+    // Do stuff with the class!
+    let echo_fut = async {
+        loop {
+            class.wait_connection().await;
+            info!("Connected");
+            let _ = echo(&mut class).await;
+            info!("Disconnected");
+        }
+    };
+
+    // Run everything concurrently.
+    // If we had made everything `'static` above instead, we could do this using separate tasks instead.
+    join(usb_fut, echo_fut).await;
+}
+
+struct Disconnected {}
+
+impl From<EndpointError> for Disconnected {
+    fn from(val: EndpointError) -> Self {
+        match val {
+            EndpointError::BufferOverflow => panic!("Buffer overflow"),
+            EndpointError::Disabled => Disconnected {},
+        }
+    }
+}
+
+async fn echo<'d, T: Instance + 'd>(class: &mut CdcAcmClass<'d, Driver<'d, T>>) -> Result<(), Disconnected> {
+    let mut buf = [0; 64];
+    loop {
+        let n = class.read_packet(&mut buf).await?;
+        let data = &buf[..n];
+        info!("data: {:x}", data);
+        class.write_packet(data).await?;
+    }
+}

examples/stm32u0/src/bin/wdt.rs

@@ -0,0 +1,41 @@
+#![no_std]
+#![no_main]
+
+use defmt::*;
+use embassy_executor::Spawner;
+use embassy_stm32::gpio::{Level, Output, Speed};
+use embassy_stm32::wdg::IndependentWatchdog;
+use embassy_time::Timer;
+use {defmt_rtt as _, panic_probe as _};
+
+#[embassy_executor::main]
+async fn main(_spawner: Spawner) {
+    let p = embassy_stm32::init(Default::default());
+    info!("Hello World!");
+
+    let mut led = Output::new(p.PA5, Level::High, Speed::Low);
+
+    let mut wdt = IndependentWatchdog::new(p.IWDG, 1_000_000);
+    wdt.unleash();
+
+    let mut i = 0;
+
+    loop {
+        info!("high");
+        led.set_high();
+        Timer::after_millis(300).await;
+
+        info!("low");
+        led.set_low();
+        Timer::after_millis(300).await;
+
+        // Pet watchdog for 5 iterations and then stop.
+        // MCU should restart in 1 second after the last pet.
+        if i < 5 {
+            info!("Petting watchdog");
+            wdt.pet();
+        }
+
+        i += 1;
+    }
+}